There are two independent ballast in the system and are not linked other than by power cord. The fixture are tested a few time during assembly to make sure there are no problems.
Can you send a few photos of the setup and installation to
[email protected]? I can send you some troubleshooting details to check the T5 lamps. These are all new tested lamps?
With them flashing and turning off it would indicate the ballast are activating the end of life protection. This happens when one of the two lamps are not working or functioning correctly.